The present invention relates to a coaxial electrical connector. More specifically, the present invention relates to a coaxial electrical connector attached to a circuit board for connecting with a mating coaxial electrical connector in a direction perpendicular to a surface of the circuit board.
A conventional coaxial electrical connector that is attached to a circuit board for use has been disclosed in, for example, Patent Reference.
Patent Reference Japanese Patent Publication No. 2006-66384
In Patent Reference, the conventional coaxial connector having a male type central conductive body is attached to one of two opposing circuit boards, and a coaxial connector having a female mold central conductive body is attached to the other circuit board. The two circuit boards face each other. The two coaxial connectors are then fitted into each other to connect the circuit boards.
According to Patent Reference, an outer conductive body of each coaxial connector has a fitting tubular portion. The fitting tubular portion is made of a round metal sheet in a cylinder shape. Further, an attachment portion for the circuit board protrudes from the fitting tubular portion outwardly from a radial direction to be integrated with the fitting tubular portion.
The fitting tubular portion is provided with a slit in a part thereof along a circumference direction. The slit extends in parallel to an axis line of the fitting tubular portion. The slit elastically expands a diameter thereof in a radial direction, so that the fitting tubular portion easily fits with a fitting tubular portion of the mating connector.
In the conventional coaxial connector disclosed in Patent Reference, the attachment portion that is integrated with the fitting tubular portion of the outer conductive body protrudes outside of the radial direction from the fitting tubular portion. Further, an area inside of the fitting tubular portion is not covered by the outer conductive body, and a contact portion of the central conductive body is not shielded enough in this area. Accordingly, a pad for shielding must be formed in a corresponding area of the circuit board in order to obtain a shielding effect.
Specifically, when the contact portion of the central conductive body is a female mold, the contact portion must be provided with a spring property to be able to elastically deform. Further, it is difficult to hold the central conductive body in a dielectric body through an integrated molding while maintaining a freedom of elastic deformation.
Accordingly, in the connector disclosed in Patent Reference, the contact portion of the central conductive body is inserted into a hole portion that pierces a center of the dielectric body from top-to-bottom. A connection portion to be connected to the circuit board is bent in an L character shape on a lower edge of the contact portion, and is exposed while extending along a bottom surface of the dielectric body.
Accordingly, when the connection portion is connected to the circuit board with solder, solder flux may rise from the connection portion and adhere to the contact portion. As a result, the solder may deteriorate a contact property of a connection with the mating connector at the contact portion.
When two circuit boards are connected through the coaxial connector, one of the connectors must have a central conductive body of a female mold. Accordingly, the connector disclosed in Patent Reference has the problem described above.
In view of the problems described above, an object of the present invention is to provide a coaxial electrical connector for a circuit board with an improved shielding property and capable of preventing solder flux from rising when soldered.
Further objects and advantages of the invention will be apparent from the following description of the invention.